Diazepam (Apaurin)
Mechanism of action
Benzodiazepine and anticonvulsant.
Acts on benzodiazepine receptor via GABA-A receptor and enhances its inhibitory effect through increased frequency of chloride channel opening.
Causes sedation, anxiolysis, anterograde amnesia, muscle relaxation and has an anticonvulsant effect. At higher doses causes respiratory depression. Effects are dose-related.
Indications and dose
Side-effects
Vomiting
Respiratory depression
Confusion
Drowsiness; excess sedation
Paradoxical agitation (more common in elderly)
Cardiovascular depression
Precautions
Metabolised by liver - may need reduced dose in liver failure.
Additive effects with other CNS depressant drugs.
Respiratory and cardiovascular depression can be more profound in cardiopulmonary disease.
Pharmacokinetics
Routes: Oral, intravenous, intramuscular, by rectum
Onset: 1-3 minutes (IV); 2-10 minutes (rectal)
Duration: 15-30 minutes
Bioavailability: >90%
Metabolism: Hepatic
Half-life of elimination: Intramuscular: 60-70 hours; Intravenous: 33-45 hours; Oral/Rectal: 45 hours; NB: Diazepam accumulates on multiple dosing
Excretion: Urine
Reversal agent
Flumazenil - benzodiazepine antagonist.
Directions for administration
Diazepam is adsorbed by plastics of infusion bags and giving sets.
Dilute in 5% glucose or 0.9% sodium chloride.
Medicinal forms
Tablet - 5 and 10 mg.
Oral suspension
Oral solution
Solution for injection - 1 vial = 10 mg in 2 ml.
Emulsion for injection
Enema
References
